Prokaryotic Diversity

Free Response

Describe briefly how you would detect the presence of a non-culturable prokaryote in an environmental sample.


As the organisms are non-culturable, the presence could be detected through molecular techniques, such as PCR.

Why do scientists believe that the first organisms on Earth were extremophiles?


Because the environmental conditions on Earth were extreme: high temperatures, lack of oxygen, high radiation, and the like.

A new bacterial species is discovered and classified as an endolith, an extremophile that lives inside rock. If the bacteria were discovered in the permafrost of Antarctica, describe two extremophile features the bacteria must possess.


Possible answers include:

  • Psychrophile
  • Hypolith – survival in low humidity/water environment